Effects Of BBMP Implantation For Preventing From Fracture After Postmenopausal Osteoporosis

Objective Evaluation on the effects on preventing from fracture after postmenopausal osteoporosis due to partial implantation of BMP .It contributes to a new solution to preventing from fracture of postmenopausal osteoporosis.Method 60 three months old female Wistar rats were selected and ovariectomized ,out of which 44 rats were finally chosen by Dual-energy X-ray absorptionmetry and served as experimental model with freezable bBMP implanted partly in the right femoral neck. The left femur neck of the same rat was taken as control of implanted BSA. Specimens were obtained at the 4^th week and 8^th week after the implantation when rats was sacrificed .The thickness of cortex ,bone density and biomechanical properties were tested by CT ,Dual-energy X-ray absorptionmetry and biomechanical test.Result All the 44 selected rats entered the result analysis. Bonemorph: At the 4^th week, the bone trabecula of experimented femoral neck (the right side) was found complete and good in consistency, while the bone trabecula on the left side was found scarce, not in consistency and incomplete. At the 8^th week, the bone trabecula on the experimented femoral neck became densified and its quantity increased and connected into net-shaped structure with even distribution. While the bone trabecula on the left side became scarce, thinner and the distance got enlarged. Medullary cavity of bones became bigger. The cortex thickness , BMD and biomechanical test: At the 4^th week, no difference was found in thickness of cortex between the two sides, while an increase was shown in the right femoral neck (P<0.05) .At the 8^th week, the cortex thickness, BMD and biomechanics on the right side increased more than it on the left side (P<0.05) with obvious difference. Expression of c-fos,c-jun in the left side are lower than one in the right side by immunohistochemistry detection. (P<0.01)Conclusions 1. bBMP implantation can improve the cortex thickness, bone density and strength of the femoral neck in ovariectomized rats and may be effective in preventing postmenopausal osteoporosis fracture of femoral neck .2. bBMP implantation can inhabit expression of c-fos,c-jun, which can draw the conclusion that inhabited osteoblast apoptosis could decrease the development of osteoporosis.